Twitter for iPhone has been updated to v3.0.1 which brings iOS 4 support and also supports the iPhone 4’s Retina Display. Twitter for iPhone can now take advantage of the App Switching (aka multitasking) feature in iOS 4.0 and can send tweets in the background if switch out of the application. This includes photos and videos!

What’s New in Twitter for iPhone 3.0.1

More secure tweeting and photo/video posting (now using Oauth for all communications with Twitter and hosting partners)

Support for iOS 4: Tweets will send in the background if switch out of the application. This includes photos and videos!

Support for iPhone 4’s Retina Display

Bug fix for stuck top tweets

You can download Twitter for iPhone app from iTunes App Store for Free! [iTunes Link]